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Performance evaluation of impulse radio UWB systems with pulse-based polarity randomization

In this paper, the performance of a binary phase shift keyed random time-hopping impulse radio system with pulse-based polarity randomization is analyzed. The effects of interframe interference and multiple-access interference on the performance of a generic Rake receiver are investigated for asynchronous systems in frequency-selective environments. A key step is to model the asynchronous system a

Fluorescence FE II lines as traces of fast outflows of white dwarf winds

A set of equations are put into a code forming a procedure to derive intensities of fluorescence lilies based on both physical properties of the fluorescent plasma and its location relative to the origin of the pumping emission. In a first test, the code is applied to symbiotic stars, and effort is made to explain the circumstances under which the two known Fell channels pumped by C IV are activat

Control of Cracking due to Imposed Strains in Concrete Structures.

Popular Abstract in Swedish Sprickkontroll av betongkonstruktioner är ett viktigt men ofta styvmoderligt behandlat område. Detta gäller speciellt för konstruktioner utsatta för tvångsbelastning, t ex temperaturbelastning eller krympning av betongen i kombination av yttre tvång. Syftet med sprickkontroll kan antingen vara att undvika sprickor eller att begränsa sprickbredden. Syftet med denna forskThis thesis is concerned with crack control due to imposed deformations in concrete structures. The objective of crack control may either be to prevent cracking or to limit the crack widths. The aim here is to increase the knowledge in both fields for some common structures. Five papers are included and the three last concern crack development. Paper I: Friction tests are performed for slabs cast

Design and validation of a universal 6D seam tracking system in robotic welding based on laser scanning

This paper presents the design and validation of a universal 6D seam tracking system that reduces the need of accurate robot trajectory programming and geometrical databases in robotic laser scanning. The 6D seam tracking system was developed in the flexible unified simulation environment, integrating software prototyping with mechanical virtual prototyping, based on physical experiments, The vali

Brits in Space

Analys av den brittiska science fiction-filmen under 1960- och 1970-talen med filmen Moon Zero Two som exempel.

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Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional and magnification renal angiography using lanthanoxibromide screens MR 600 and carbon fibre plate in filmchangertop have been made. The mean skin dose in magnification technique was 0.56 rad./film with focus-skin distance of 35 cm, FFD 1 m, 85-90 kV and sagittal diameter of abdomen of 20 cm. The combin

Brain capillary density and cerebral blood flow after occlusion of the middle cerebral artery in normotensive Wistar-Kyoto rats and spontaneously hypertensive rats

OBJECTIVE: In order to elucidate why spontaneously hypertensive rats (SHR) develop larger brain infarcts distal to an arterial occlusion than normotensive Wistar-Kyoto (WKY) rats, we determined the surface and volume densities of cerebral capillaries, and the regional cerebral blood flow distal to an arterial occlusion in SHR and WKY rats. DESIGN: Occlusion of the middle cerebral artery was chosen

Raised serum S100B levels after acute bone fractures without cerebral injury

Background: S100B, a protein abundant in astroglial cells within the central nervous system, has been shown to increase in cerebrospinal fluid and serum after various neurologic diseases. However, the cerebral specificity of S100B has been questioned. This study aims to show serum S100B levels after uncomplicated bone fractures in patients without current or prior neurologic diseases. Methods: Blo

Electron Dynamics within Ru-2,2'-Bipyridine Complexes - an N1s Core Level Study

The dynamics of electron transfer within an excited ruthenium complex as well as between a ruthenium complex and a nanostructured TiO2 film is addressed on the core hole few femtosecond lifetime scale. The ruthenium complexes studied are Ru(bpy)32+·2Cl− (where bpy is 2,2′-bipyridine) as well as Ru(bpy)2(dcbpyH2)2+·2PF6− (dcbpy is 4,4′-dicarboxy-2,2′-bypyridine) anchored to a nanostructured TiO2 su

Patrullerande polisers yrkeskultur

Popular Abstract in Swedish Det övergripande syftet för denna avhandling är att bland patrullerande poliser undersöka förekomst och karaktär av en yrkeskultur, som går utöver eller står i motsättning till polisens officiellt sanktionerade samhällsmandat bl.a. i termer av den inriktning, de prioriteringar och det regelverk som omger polisarbetet. Begreppet yrkeskultur står här för kollektiva mönsteUsing ethnographical methods, this thesis examines the prevalence and character of an occupational culture among patrolling police in terms of frames of reference, conduct and attitudes, a culture which overrides or is in opposition to the official mandate of the police force. It is suggested that the occupational culture of the patrolling police should not be regarded as a homogenous culture but

Cost-equivalence of different osteoporotic fractures

Methods. Among 985 Olmsted County, Minnesota, residents who experienced an osteoporotic fracture (distal forearm, humerus, clavicle/scapula/sternum, ribs, vertebrae, pelvis, hip, other femur or tibia/fibula [the latter in women only]), we estimated the incremental cost of direct medical care in the following year compared with age- and sex-matched controls without a fracture randomly sampled from